Gun lubrication



o. B; GRAHAM.

GUN LUBRICATION.

APPLICATIUN FILED JULY 2.1919.

Patnted Aug. 31

lyrix/YW@ x x y vfrom being pulled 4or blown off of UNITED as'rATEs PATEN'I" OFFICE.

OLIVER B. GRAHAM, 0F CLEVELAND, OHIO, ASSIGNOR TO l TION, 0F NEW YORK,` N. Y., A CORPORATION ATO-ORDNANCE CORPORA- OF NEW YORK.

GUN LUBRICATION.

Specification of Letters VPatent.' -Patellted Al1g 31, 1920- Appueation filed July 2, 1919. serial No. 308,222.

To all whom t may concern Be it known that I,v OLIVER B. GRAHAM, a citizen of the United States, and resident of,Cleveland, Ohio, in the county of Cuyahoga and State of Ohio, have'invented new and useful Improvements in Gun Lubrication, of which thefollowing is al specification. 4 5

This invention relates to guns and more particularly to 4automatic firearms, either semi-automatic or full automatic, the objects of the invention being to reduce the friction on the various sliding orrubbing parts of guns, thereby reducing Wear on the parts and increasing the speed of operation, to render the operation of the working parts -of guns entirely uniform and reliable, to

maintain constant the forces of the breech pressure acting on thebreech locking mechanism in the case of automatic guns of the type which are unlocked directly in response to the breech pressure, to prevent thev heads cartridges in the firing chambers, to render the extraction of cartridges free and uniform, to increase Ithe velocity of the projectiles, to re-- duce the Wear and heating of the barrel, and

generally to improve the operation of guns, 4

' partic-ularly automatic guns.

The invention consists in lubricating the contacting surfaces between the firing chamber and the cartridge cases so that the empty cases will not stick in the chamber after firing but will slide out freely and uniformly, lubrication of the cartridge cases being especially important inv automatic guns where the uniformity the breech closing mechanism depends largely upon the free and uniform extraction of the cartridge-cases and where the extraction may take place while the residual .gas pressure tending to expand the cartridge case against the-.wall of the firing chamber is still hi h. The invention also consists in lubricating the sliding surfaces between the various parts of the breech action and betweenthe breech action and the receiver, this-also being particularly desirable in automatic guns where excessive or variable friction in the breech action renders the operation erratic and unreliable. Fur-v ther the invention consists in lubricating the contacting surfaces between the projectiles and the bore of the barrel, this being espe-` cially important in automaticl guns where of operation of the projectiles are fired at a rapid rate and `where itis desirable to maintain the friction between the projectiles and the bore uniform in order to maintain uniform the breech' pressure reacting on the breech closure.

The invention also consists in effecting the aforesaid lubrications by a single means by locating the lubricating means in a novel position on the gun and by timing its action in a unique manner with the cyclic operation of .the gun. I lhave found that lubricant may be supplied to the firing chamber of a gun, either before each cartridge is inserted thereinto or from time to time at 4'suitable intervals, in such manneras not only to'lubricate the contacting surfaces between the cartridge cases and the firing chamber but also to lubricate the sliding surfaces' of the breech 'action and the contactmg surfaces between the projectiles and the bore of the gun. This is preferably ef fected by ejecting lubricant into the firing chamber, either in the form of asprayl or otherwise, immediately inv advance of each cartridge so `that-,lubricant will be distrib uted over both the projectile and the case Aof each cartridge as it enters Athe firing thereby carrying lubricant from the" firing 95 chamber and depositing same on the breech action. The' spray of lubricant into the firing chamber may be so timed with respect to the flow of gas from the mouth of the firing chamber that apart of the lubricant 100 will be carried back to the breech action by the gas before it is deposited upon either the firing chamber or the cartridge entering the firing chamber. The means for ej'ecting the lubricant into the gun is timed to op-v 105 erate at the proper instant inthe cycle of operation, particularly in relation to the position of the cartridge in transit to the firing chamber and to the `flow of gas from the mouth of the firing chamber, andl this is 110V preferably effected by actuating the ejector by or with the breech closure.

In order to illustrate the nature ofthe invention a specific embodiment thereof is illustrated in the accompanying drawings in which,-

Figure 1 is a side elevation of the central part of a gun having the invention applied thereto, portions of the gun being shown in vertical longitudinal section and the receiver being broken away to show the breech action in elevation;

' Fig. 2 is a horizontal longitudinal section on line 2--2 of Fig. 1;

Fig. 3is a vertical transverse section on line 3 3 of Fig. 1; l

Fig. 4 is an enlarged left side elevation of a part of the lubricating means; and

Fig. 5 is a vertical transverse section 0n line 5-5 of Fig. 4.

The gun illustrated in the drawings for the purpose of showing one concrete application of my invention is a semi-automatic army rifle com rising a stock H, a

barrel A, a receiver a bolt B, an automatic bolt lock L, transmitters T, extractor E, ejector J, a bolt stop Y, a bolt stop spring N, a bolt. stop washer W, recoil springs Q, a,

retractor 11,A a retractor pin t, a safety catch s, a trigger U, a` trigger bar V, atripper pawl X, etc. This rifle is fully described in my copending application Sr. No. 308,223 filed on even date herewith, and further description thereof is unnecessary for the purpose of the present application.

The lubricating means and the combination of the lubrication means with a gun, forming the subject-matter of the present invention will now be described.

tion chosen for the purpose of illustration comprises in general a lubricant reservoir 1, a pump 2, a duct 3 voir to the pump, a duct 4 leading from the pump' to the firing chamber, and a connector 5 connecting the duct 4 to the firing chamber.

The reservoir 1 is shaped as shown in Figs. 1 to 3 and is provided with flanges 6 and 7 adapted toslide behind fianges on the receiver as shown in Fig. 2 for the purpose of mounting the reservoir on the receiver, the reservoir sliding upwardly intov the receiver when the stock is removed and being 4held in position by the stock or vother suitable means. For the purpose of filling the reservoir from time to time a filling open- 'ing is provided in the bottom in alinement with the cartridge magazine opening in the stock so that the reservoir may be filled without removing the stock by inverting the gun', a plug 8 being provided to close this opening. The 'duct 3 and a part of the duct 4 are formed in the walls of the reservoir 65 (Fig. l), and a pump chamber is provided The particular embodiment of my inven leading from the reserchamber at the top.

in the rear end of the reservoir in communication with the ducts 3 and 4, the chamber being closed on the outside by a cover plate 20 extending throughout the length and depth of the reservoir and being soldered or welded or otherwise secured in place.

The connector 5 comprises a tubular member having a conoidal head adapted to seat in a conoidal recess in the bottom of the firing chamber and a base adapted to have the pipe 4 secured therein. The central portion of the connector has a smaller diameter and is surrounded by a coil compression spring 11 which bears against the under face of the head at its upper end and at its lower end bears against-a washer 12 bifurcated to straddle the connector, the washer 12 sliding from the front into a guideway in the bottom of the forward end of the receiver and being retained in position by the stock when the stock is attached to the gun. Thus the conoidal head of the connector is held tightly seated in the conoidal lubricant as 1t is delivered' to the firing chamber; and the restricted passageway communicates with the opening in the wall of the firing chamber which is inclined for-v l wardly at the proper angle to eject the lubricant obliquely into the firing chamber, preferably in the form of a spray.

The lubricant pump comprises a pair of spur gears 9 and 10 meshing together in the chamber in thel rear end of the reservoir, which ychamber is substantially no larger than is just suflicient to receive the gears.

As shown in Fig. 1, the duct 3 leading from 105 the reservoir communicates with this chamber at the bottom, and the duct 4 leading to the firing chamber communicates with the As the gears are rotated in the direction of the larrows (Fig. 1) lu- 110 bricantis carried from the bottom to the top of the chamber in the spaces between the teeth and the end walls of the chamber, the gears fitting the chamber sufficiently snugly to prevent much if any lubricant from leaking back along the gears especially when the pump is acting against relatively low pressures. Oil is prevented from being carried from the top to the bottom of the chamber between the gears, at least n appreciable ting 1n a square opening in the ratchet clockwise direction wheel 14, a circular portion upon which the ratchet arm 16 is rotatably mounted, a threaded end, and a smooth portion adjacent the threaded end, the cross-sectional size of the various portions being such that the stud shaft may be inserted from the right (Fig. 5). The threaded portion of the opening in the ratchet arm 16 is substantially equalin length to the smooth portion of the stud shaft adjacent the threaded end thereoffso that after being threaded on the stud shaft to the position shown in Fig. 5 the ratchet arm is free to rotate on the stud shaft with substantially no lost-motion either axially or radiallyand can only be removed by oppositely rotating the two parts relatively to each other.4 In operation the relative rotation is always in the same instead of the opposite direction, so that the ratchet arm is thus automatically prevented from becoming displaced from the stud shaft. The ratchet 17 has a lug 19 extending outwardly through a slot in the side of the hollow ratchet arm into engagementv with the ratchet wheel. The upper end of the hollow ratchet arm is closed by a plug 21 fast therein. A light spring 22 `is provided to hold the ratchet in contact with a tooth of the ratchet wheel except when the ratchet is forced in a (Fig. 4) as will hereinafter be described.4 y

According to the present invention, in one of its aspects, the lubricant pump is arranged to be actuated by some moving part of the breech action during the opening or:

closing of the breech action to deliver lubric ant to the firing chamber (or to other desiredy part or parts of the gun) each `time the gun 'is fired or loaded, and as illustrated in the drawings the ratchet arm 16 projects upwardly into the path of-a lug 23 on the right-hand side of the bolt and also in the path of the rear face `24 (Fig. 1) of the lock L. As the bolt .is advanced by recoil v s )rings Q. the lug engages the rear side of the ratchet arm and sharply rotates the arm to advance the ratchet wheel one notch, the spring pawl 15 holding theratchet wheel in advanced position against the back pressure of the lubricant. The lug 23 then passes over the ratchet arm, the arm being held down out of the path of the lug upon the recoil of the bolt by means of spring 22. When the bolt automatically recoils, or is manually retracted, the face 24 of lock L engages the forward Side of the ratchet arm to return it to upright position, thereby bringing the ratchet 19 into engagement with the next ratchet tooth. IThe face 24 engages the ratchet arm on the recoil owing .f tothe fact thatthis. face extends lower than bolt is completely retracted the face 24 of the lock stops in the plane of the forward side ofthe arm when in upright `-position.

Thus each time the bolt is plunged forward by the recoil springs the pump is sharply actuated to produce a brief but sharp pressure on the head of lubricant between the pump and the firing chamber. lf the orifice and pump are properly designed this pressure will cause a small amount of oil to be sprayed into the firin chamber. ,By4 locating the actuating portlon of the pump and the actuating portion of the breech action (the lug 23 in the illustrated example) in the proper positions the lubricant may be ejected at any desired instant in the cyclic operation of the breech action, and as illustrated the lubricant is e'ected at the time the cartridge is entering t e firing chamber so that the cartridge passes through the spray of lubricant and is coated thereby. From the foregoing itwill be evident that in its more speci c aspect, theinvention also involves the following characteristics: the pump'arm 16 is inoperative when in its forward position inasmuch as it is out of the path .of the actuating shoulder of bolt lugchamber,-'.and vmeans actuated by the breech closure in its closing movement to force lubricant through said duct, said automatic breech closure and ammunition feeding means and lubricant forcing means being j synchronized to spray lubricant on the ammunition in transit to the ring chamber.

2. A gun comprisingA a breech closure, means for lubricating parts of the gun each time the breech closure is actuated, said means vhaving `an operative and an inoperative position, and mechanism for actuating said means V closure, leaving the means in inoperative position, and then returning the means to operative lposition during the opposite move-l ment of the closure.

3. A gun comprising a breech closure, means lfor lubricating parts of the gun, said meanshaving an actuating part adapted to be moved into and out of operative relationship to said closure, and means for auto-` matically moving said part into said o erative position durin one movement o the breech closure so t at the means may' be actuated during the opposite movement of the closure. I

during one movement of the 4 4. A gun comprising a breechvclosure,

means for lubricating parts of the gun, said,

means including a gear pump and ratchet mechanism for actuating the pump, and means for automatically advancing said ratchet mechanism during one movement of the closure and retracting the mechanism durinlgxthe opposite movement of the bolt.

5. gun comprising a breech closure, means for lubricating parts of the gun including a gear pump, ratchet mechanism for actuating said pump, said mechanism having an arm adapted to actuate the pump when moved in'one direction and to move independently of the pump in the opposite direction, and said closure having shoulders respectively arranged to move said arm in opposite direction during the open inlfrj and closing movement of the closure.

igned by me at Cleveland, Ohio this twenty-fourth day of June 1919.

" OLIVER B. GRAHAM. 

